Air Quality Index and Respiratory Symptoms among Garri Processing Workers in Ogbomoso, Nigeria

Epidemiological studies have linked morbidity and mortality of individuals to exposure to atmospheric gaseous and particulate matter especially fine particles (PM2.5) and coarse particles (PM10).The process of garri (cassava crisps) production (frying with firewood) is associated with production of gaseous and particulate matter which contribute to ambient particulate matter air pollution. The objective of this study was to determine the impact of air quality indices on the prevalence of respiratory symptoms among the garri processing workers in Ogbomoso.

A comparative cross-sectional study was carried out among 351 garri processing workers in Ogbomoso as subjects and 351 residents of Ogbomoso metropolis as controls that were age, sex and height-matched. A semi-structured questionnaire was used to obtain sociodemographic profiles and respiratory symptoms of participants and document physical examination findings. Particulate matter counter was used for air quality sampling.

The mean age of subjects was 41.7 ± 14.9 years and that of controls was 41.6 ± 14.7 years (p =0.960). The two groups were also matched for socioeconomic status, sex and height. Prevalence of respiratory symptoms was higher at 48.4% among the garri workers than the control group which was 29.1% (p<0.001). Cough was the predominant symptom with a prevalence of 29.3% and 10.5% among the subjects and controls respectively. The mean count of PM1.0 in garri processing locations was significantly higher than that recorded in Ogbomoso metropolis; 73.77±42.08 vs 15.04±6.66mg/m3 (p<0.0001).

Garri processing work is associated with significant increase in ambient air pollution and increased prevalence of respiratory symptoms among the workforce compared to the control population. Effective preventive strategies including education and provision of safety masks may reduce the occupational hazards associated with garri processing factory workers in Nigeria.